Roadway guard rail barrier



March 14, 1967 H. s. SMITH ROADWAY GUARD RAIL BARRIER 4 Sheets-Sheet lINVENTOR. Hf'A/,QyjUc/15M/ rH.

Filed 0G13. 8, 1965 March M, 1967 H. s. SMITH ROADWAY GUARD RAIL BARRIER4 Sheets-Sheet 2 Filed 0G15. 8. 1963 NVENTR. INPVUCHM/ TH.

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United States Patent Oli ice 3,308,724 ROADWAY GUARD RAIL BARRIER HenrySuch Smith, Raritan Road, P.O. Box 55, Roselle, NJ. 07203 Filed Oct. 8,1963, Ser. No. 315,739 13 Claims. (Cl. 94-1.5)

This application is a continuation-in-part of a copending applicationNo. 55,534, filed Sept. 12, 1960, now abandoned, which in turn is aoontinuation-in-part of abandoned applications 660,129, tiled May 20,1957 and Ser. No. 584,789, filed May 14, 1956.

The present invention relates to roadway guard rail barriers, for use inboth side-of-the-road and center-ofthe-road applications, and as to thelatter to provide a center roadway guard rail barrier for separatinglanes of traffic moving in opposite directions.

`One of the greatest single causes of traffic fatalities, the head-oncollision, can be virtually eliminated by an adequate middle stripseparating the opposin-g lanes of traffic.

In the prior art, means have occasionally been employed for separatinglanes of trafc moving in opposite directions. For example, a centerdividing stnip of ground for the roadway has sometimes been used. Such astrip, however, in order to be effective, must be quite wide and,according to highway engineers, preferably at least fifteen feet wide.Obviously, a st-rip of this nature takes up a great deal of the roadway.On new constructions, such a strip would entail a greater landacquisition cost, or with a given land acquisition cost, narrowershoulders and greater danger of roadside accidents. `On existing roads,the addition of a center strip of even modest proportions, protected byconcrete curbing, has been impractical, because it would narrow theexisting lanes of trafc, and still further increase the alreadyexcessive lateral dangers of the highway to the motorist.

Another means which has been employed for the purpose of separatingoppositely moving traffic is the installation of a high center concretecurb. Here, however, much time and expense are involved in laying such acurb and the use of cumbersome concrete fonms is required. These formsmust be set, secured, and subsequently removed, which process, combinedwith the related ones of installing reinforcing steel and pouringconcrete, either requires the work to proceed on a long length ofroadway simultaneously, with a -great demand on the contractorsequipment and manpower, or requires very slow progress to be made withconsequent continuing delay to the improved ow of tratlic. Such aconcrete curb must be very wide at the bottom to resist being overturnedby the force of a collision. Further, by the very nature of concreteowing to its inherent weakness under tension stress, it is suflicientlystrong only when present in considerable mass, and 4also adequatelysteel reinforced. That is, the very best designed center curb must beeither unnecessarily wide and bulky, having the effect of furtherdisplacing the traic flow towa-rd the crowded sides of the road, or besubject to sacrifice of strength at the top. 11n the latter instance,the c-urb may fail to retain under impact the desirable contournecessary most effectively to prevent the crossing thereof by vehiclesunder any conditions of driving error or collision impact. That is, suchcurbs may frequently be jumped unless extremely high, and consequentlyrunwieldy and forbidding from the motorists point of view. Such highunwieldy curbs cause the motorist to instinctively pull away to avoidvehicle damage, and thereby have the effect of displacing tra'ic towardthe crowded sides of the road. Also, in addition to the normal repellingeffect of a high concrete curb on the driver, there is added the ele-3,308,724 Patented Mar. 14, 1967 the existing high concrete curbs, whichstill further tends to displace traic flow toward the sides of the road.

Attempts in the prior art to obviate some of the disadvantages ofconcrete face barriers have resulted lin various designs of elastic oryielding rails, bars, ropes, cables, link fences, woven wires or thelike, used simply or in combination, supported on posts, pedestals orother essentially discrete supports which permit yielding upon impactbetween supports. Such yielding, whether elastic or permanent, on thepart of prior art barriers can form a pocket or bag-like indentation inthe prior art barrier just before the next support beyond the point ofimpact in such way as to trap the forward component of motion and eitherneedlessly injure or kill the occupants of the colliding vehicle at theinstant of impact, or throw the vehicle over into a series of rolls orcatapulting motions which often lead to the most severe type of multiplevehicle accident.

vOne object of the present invention is to provide a center roadwayguard rail barrier of ideal and aesthetic proportions and which is atthe same time of simple and inexpensive construction.

A further object of the invention is to provide a guard rail barrierwhich may be so easily and rapidly installed without special contractorsequipment, that highway departments lmay install it with maintenancepersonnel, paid from general mai-ntenance funds, immediately as highwayhazards develop.

A further object of the present invention is to provide a center roadwaybarrier of such conldenceegiving stability that highway motorists cansafely divert their presently-demanded attention from oncomingother-lane vehicles, to their own side of the road, with a consequentincrease in safety to other drivers and pedestrians and a reduction insame-direction and off-road accidents.

A further object of the invention is to provide a guard rail ba-rrierwholly without projection or irregularity which could impede the forwardmotion of a vehicle coming in collision with it.

'A further object of the present invention is to provide a centerroadway guard rail barrier which will prevent collisions betweenvehicles moving in opposite directions in adjacent traffic lanes bykeeping said vehicles in their proper lanes, regardless of driverinattention, mechanical failure, or any lateral component of motiontoward the other on-coming traic lane which could be caused by anycombination of collision circumstances in the drivers lane or acting onthe drivers vehicle.

A still further object of the presen-t invention is to provide a railbarrier of the simplest possible structural elements, which may bejam-locked to the road surface and the opposite sides to each other,regardless .of the type of condition of roadway construction, which railbarrier may be connected with downwardly tensioned bolts or tie rods tothe highway pavement or `ground beneath, thereby functioning inconjunction with the pavement to utilize the mass of the highwaypavement inI opposition to a vehicles lateral component of force incollision with the barrier.

A further object of the invention is to propide a guard 'rail Ibarriermember the reinforcing of which is external to the member, so that witha minimum use of material a maximum stiffness of the member may beobtained, and the force of a collision may be absorbed by maximum lengthof member.

A still further object of the invention is to provide a guard railbarrier so effectively narrow that use of it will be practical acrossnarrow bridges and in similar areas where any median separating striphas been previously impossible because of space limitations.

A further object of the invention is to provide a rigid when installed,yet easily benda-ble during installation solid rail barrierwhich can beapplied on sharp highway curves.

A further object of the invention is to provide a guard rail barrierwhich, when filled with concrete in accordance with a preferredembodiment, will act as its own permanent concrete form, and may befilled with concrete by gravity by the continuous progression ofsemi-automatic filling equipment.

A still .further object of the invention is to provide a guard railbarrier in which each side, locked in an inclined position to the other,acts to brace and support the other side against collison damage.

These and other objects of the present invention will be apparent from areading of the following specification thereof, taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a top plan view of a center roadway guard rail barrier memberin accordance with one embodiment of the invention;

FIG. 2 is a side elevation of the interior of one of the skin plates astaken at 2 2 of FIG. 1, the positioning of the upper and lower tie clipsfor attaching the opposite plates Ibeing shown with their alternativelyhigh and low stations indicated diagrammatically as discussed below;

FIG. 3 is a view in perspective of the member of FIG. 1 filled withconcrete in accordance with the preferred embodiment;

FIG. 4 is a sectional View taken along line 4 4 of FIG. 1; while FIG. 4ais an enlarged, fragmentary, s ectional view of a portion of FIG. 4showing on an enlarged scale, the overlapping clips integral with theside plates respectively employed for bolting and maintaining in properalignment the side plates to the -roadway as discussed below;

FIG. Sis a sectional view similar to FIG. 4, but showing amodifiedformof the invention;

FIG. 6 is a sectional View taken along line 6 6 of FIG. 4;

FIG. 7 is an enlarged fragmentary sectional view of the top portion .ofa modified guard rail in accordance with the invention, showing twopossible forms of trough clips carried by the skin plates and ananchoring lug for interconnecting the plates;

FIG. 8 is a fragmentary Vsectional viewV similar to FIG. 7, illustratinga modifiedv trough clip and anchoring lug construction;

FIG.,9 is also a fragmentary, sectional view similar to FIG. 7,illustrating a still further trough and anchoring lug construction;

FIG. l() is a perspective View of the trough clip at the left of FIG. 7;

FIG. 1i is a perspective View of the trough clip at the right of FIG. 7;

FIG. 12 is a perspectiveview of the anchoring lug of FIGS. 7 and 8;

FIG. 13 is a view in vertical section` of a preferred form of theinvention; and

FIG. 13a Iis a fragmentary sectional view as taken at 2 2 of FIG. 13.

Referring to the FIGS. 1 to 4 inclusive, there is shown a center roadwayguard rail, consisting of two identical metal skin plates land 2. Eachskin plate is formed of a straight, or flat, inclined side 3, which sidemerges into a relatively short upwardly and outwardly curving neckportion 4, the latter merging into an -upper reversely, i.e., inwardly,curved head portion 5. The plates 1 and 2 are mounted in converselyopposed and spaced apart relation as shown and such as to provide acentral opening 6 therebetween.

Welded at regularly spaced points to the opposed inner surfaces of theneck portions of plates 1 and 2, are pairs of lopposed upper L-shapedtie clips 7a, 7b. The clips 7a, 7b are each formed of a long,substantially horizontal leg 8a, 8b, FIG. 4a, and a short, substantiallyvertical leg 9a, 9b. The short legs 9a, 9b, the outer edges of which arebevelled as at 10a to receive weld metal, are welded at top and bottomas at 10b to the skin plates, respectively, as shown. The opposed clipsof each pair are reversely positioned, so that when the two skin platesare brought together into the position shown in FIGS. 4 and 4a, the longleg 8b of one of the clips 7b, will overlie the long leg 8a of the otherclip 7a. In the sectional view shown, the underlying clip 7a is weldedto skin plate 1, and this construction may tbe said to be the lowerstation attachment of an upper tie clip 7a. The overlying clip 7b iswelded to plate 2, which construction may be said to be the upperstation attachment of .an upper tie clip 7b. If the section 4 4 of FIG.1 had been taken one station further along the guard rail, as at 4X-4X,then the long leg of clip 7a would overlie the long leg of the opposingclip 7d, and so in alternating manner from station to station along theguard rail. In the drawings, it can be seen that the upper surface 9c ofthe vertical leg 9a of the underlying clip 7a attached to skin plate 1,is at the same height as, and lines up with, the horizontal uppersurface 8c of the long horizontal leg 8b of the overlying clip 7b whichis welded to plate 2. An important element of the invention, as will beapparent subsequently is that these two level horizontal surfaces, eachat the same height above the roadway, are also at the same height as thepoint of narrowest approach towards each other of the inside surfaces ofthe outer skin plates 1 and 2 as best shown in FIG. 4a.

Also welded to the inner surfaces of the skin plates l, 2, and adjacentto their lower edges, are pairs of oppose-d tie clipsl 11a, 11b. Theseclips are substantially horizontal, flat bars welded to the plate sides3, as at 12 in FIG. 4. As in the case of the clips 7a, 7b, the clips11a, 11b, have alternating lower and upper stations, one clip overlyingthe other at the center as shown in FIG. 4. As will be shownsubsequently, the two clips 11a, 11b, are subject only to tensionstress, and therefore can be made relatively thin and somewhat bendable.Therefore, for economy and simplicity in manufacture, the two clips 11a,11b, may be welded at the same height to their respective skin plates,and the free end of the one subsequently bent down to take the lowerstation, and the free end of the other subsequently bent up to take theupper station. It is to be noted that, at a given point proceeding alongthe longitudinal direction of a skin plate as in FIG. 2, an L-shapedclip 7a at the top corresponds vertically to a station of thesubstantially horizontal fiat bar clip 11u at the bottom.

Resting upon the clips 7a, 7b, is a locking spreader washer 13, havingthe same width as the dimension of the narrowest approach of the innersurfaces of the skin plates 1 and 2 when they are positioned at maximumdistance from each other as will be subsequently explained. The clips7a, 7b, and 11a, 11b, haveraligned,

longitudinally elongated slots 14a, 14h, FIGS. 4 and 4a, at the centerline of the rail guard. Passing through the slots is a machine cappedbolt 15, threaded at its bottom at 16. The slots 14a, 14b, areAlaterally wider than the diameter of bolt 15, and are so positionedthat, when the skin plates 1 and 2 are supported loosely upon thesurface of the road 17, and placed more closely together than in thefinal structure, the bolt 15 may be easily passed therethrough by hand.However, as the skin plates 1 and 2 are forced apart to their properfinal positions, shown in FIG. 4, upper and lower slots will partiallyeclipse each other, to the extent that in the final structure, therewill be only sufficient lateral clearan-ce through the slots to permitthe bolt 15 to be in tight pinning contact with the slot sides.

The guard rail assembly of FIGS. 1-4a, incl., is assembled by placingtogether the skin plates 1 and 2 bearing the clips, so that the centerslots 14a, 14b, will be in approximate registry. Washer 13 is then heldin position in the neck of the member in loose position somewhat aboveits final secured position. The bolt 15 may then.

be inserted manually through the top opening 6 between the skin platesand thence through the manually held washer 13, and through theapproximately registered slots 14a, 14b. The bolt may then be manuallystarted into a cinch screw anchor 18 or the equivalent set below thesurface of the roadway in a previously drilled hole in the roadbed 17.As the bolt 15 is turned home by means of a wrench applied to the cap15a, the skin plates 1, 2, at height of the lower tie clips 11a, 11b,are meanwhile pushed apart to their final positions of FIG. 4, by use ofany suitable spreadingr device, and the locking spreader washer 13 isforced downward in a spreading fashion into the narrowest internaldimension of the neck portion 4 at the plane of the top of the L-shapedclips 7a, 7b. As has been previously described, the height of the pointof narrowest clearance between the skin plates 1 and 2, and of the topplane of the L-shaped tie clips 7a, 7b, is coincidental. Also, the widthof the lock washer 13 corresponds to the maximum width to which the skinplates 1 and 2 can be stretched apart as the clips 7a, 7b, separate tojam the appropriate sides of the laterally widened slots 14a, 14b,against the bolt 15. As a result, the entire assembly consisting of skinplates 1 and 2, the clips 7a, 7b, the clips 11a, 11b, the lockingspreader washer 13, the bolt 15, the cinch screw anchor 18 or itsequivalent (through threads 16), and therefore the roadbed 17, becomejam-locked together into a single structural unit. Thus, as the lockingspreader washer 13 comes down tight, it forces a spread between the skinplates and takes all play out of the tie clips.

Because of the ample clearances in the slots 14a, 14b, before thejamming down of the locking spreader washer 13, only moderate accuracyof alignment of the skin plates laterally to the roadway is necessary topermit easy manual insertion of the bolt 15. In the event that groundanchor rods on a soft roadway are to be used, a speedy installation canbe accomplished by having pairs of skin plates in full registry loweredover the protruding rods.

It should be noted that the bolt 15 (or anchor rod), will have beentightened to a pretensioned unit stress of near its elastic limit.Coincidenta-lly the lower portions of the skin plates will be underpre-compression. Which ever method f loose assembly of the skin plates,elements and washers is employed, the tightening and jamming procedureis the same, as are the stress relationships.

An important element of the invention is that by the correctlongitudinal, alternative spacing of the low and high clip stations, itis possible to assemble the opposed skin plates'in full registry, halfregistry, or quarter registry. The desirability of choice of registrywill be apparent from the further discussion below.

In constructing a guard rail for a roadway, a number of members of thekind illustrated in the drawings may be joined end to end, with theopposed skin plates 1 and 2 in full registry. This type of constructionis preferable in localities where a wide range of temperature is to beexpected. In such cases, expansion joint members may be employed betweenadjacent skin plates. For example, stamped bitumastic felt expansioniillers may be used.

Where the temperature of a locality is substantially constant, it ispreferred that the opposed skin plates be installed in a longitudinallystaggered, or 1/2 or 1A: registry position. For example, if the skinplates 1 and 2 are each 20 ft. in length, a 10 ft. or 5 ft. overlap asbetween the two plates might be provided.

Under conditions of equable temperature, the staggered position isdesirable, since it assures additional strength at the joints. Thequarter staggered or ft. overlap position will be subsequently mentionedin connection with the use of the barrier at road intersections andforks.

In order to install the guard rail on a roadway, a series of anchorholes is first drilled along the center of the roadway at intervals ofdistance equal to the spacing of the bolts 15. A spacing and alignmentjig preferably may be employed to facilitate this operation. If theroadway 17 is concrete, screw-in cinch anchors 18 may be employed. If,however, the roadway is of a soft or more yielding surface, ordinaryground anchors (not shown) should be used. In the latter case, each bolt15 would be replaced by the upward projection of a ground anchor rod,the upper end of which Iwould be cut oif and threaded by means wellknown to the trade, to accept a nut to cooperate with the lock spreadingwasher 13. When the nut is properly brought down on this ground anchorrod, the spreading, locking and jamming process as above described inconnection with the use of the bolt 15 would take place in a similarmanner. That is, the guard rail barrier of the invention can belock-secured to even an earth surfaced roadway, paving materials beingentirely absent.

Referring specifically to FIG. 5, a modification of the invention isshown, designed for roadways having a center expansion joint 20. In thisembodiment the bolts 15 extend substantially parallel to the skinplates. The cinch anchors 1'8 are set in the roadbed 17 in appropriatelyinclined positions to receive lthe threaded ends of the bolts in themanner illustrated. Also in this modification a special washer 13ahaving an inclined top surface area '13b for contact with the undersideof the bolt head is provided. The lower tie clips 11a, 11b, are providedwith additional slots at their ends adjacent to the skin plates,respectively, as at 14C, 14d, and the bolts 15 pass through theappropriate slot of each, as shown. The bolts 15 extend at alternateangles at successive stations longitudinally of the Irail guard, andhence through oppositely disposed slots 14C or 14d of the tie clips 11aand 11b at successive stations. The centers of the tie clips 11a, I11b,are fastened together at each station with a short bolt 21 of thediameter of the bolts 15. The alternate position of the bolts 1'5 isindicated by the dashed lines 15b.

It will be noted from FIGS. 4 and 5 that the positioning of the upper.-tie clips 7a, 7b, and the geometrical relationships between saidclips, the locking spreader washer 13 and 13a, and the skin plates 1, 2,are such that tightening of the bolts 15, or the ground anchor rod, ifthe latter is substituted, tends to stiflin and straighten the inclinedstraight sides of the skin plates. This is because portions of the topsurfaces 8c and 9c, FIG. 4a, of the upper tie clips, each extendhorizontally on Iboth sides of the prolongation upward of the centerline of the inclined straight side of the appropriate skin plate. Whenthe horizontal lower surface of the locking spreader ywasher is bolteddown on surfaces 8c and 9c, it maintains said latter surfaceshorizontal. Such surfaces, rigidly related by welding to the upperportions of the inclined straight sides of the appropriate skin plates,thus maintain the said upper portions in straight and proper alignment.Thus, a lower portion of the inclined straight side of a skin plateresists outward deflection, such as could be caused by a filling of thespace between the skin plates with wet concrete, in accordance with theformula for a beam fixed at one end, supported at other, rather thanthat for a simple beam as `would be the case were it not for the saidpositioning of the upper clips and the associated geometricalrelationships. This method of construction of the invention is so muchstiffer that with a given thickness of skin plate, and with a givenassumed internal pressure of wet concrete, the skin plate deflects lessthan one half as much as without such construction. Stated in anotherway, the construction of the invention permits approximately a 15%reduction of the thickness of the skin plate without increase indeflection as compared to ordinary construction.

A bolt 15 or a ground anchor rod if substituted may also be used tosecure the upright pedestal for a reflector, traffic reguation ordirection sign, or the equivalent.

With any selected alignment and skin plate registry system, butparticularly where full registry is combined with installation of therail guard over a soft earth roadway, the two locking spreader washers1-3 or 1i3a at the ends of adjacent skin plates, may be replaced with asingle joining fish-plate having its ends dimensioned and the holesinserted as for thewasher, but elongated in a longitudinal direction.This {ish-plate construction serves more rigidly to retain the skinplates in alignment and, if concrete is to be poured into the interiorbetween the skin plates, it also serves as a reinforcement.

In practice, the structure will preferably be filled with concrete.Concrete may be continuously filled into the structure through the topopening 6.

The skin plates or armor oi the guard rail of my invention arepreferably 20 ft. long, and may be made of any suitable metal, such asaluminum or galvanized or corrosion-resistant steel; or alternatively,of a suitable synthetic material such as reinforced plastic or libreglass. The tie clip stations are preferably provided every 30 inches,with the first station starting 15 inches from the left end of the skinplate as viewed in FIG. 2. Skin plates forming the outer surface of themember are preferably approximately 1A inch thick if the rail guard isto be left hollow, and approximately 1/s inch if it is to be lled withconcrete. The straight rising portions of the skin plates for thisembodiment are set at an angle of approximately 69.5 to the horizontal,this angle being desired for reasons to be set forth below. This placesthe lolwer edges of the skin plates approximately 20 inches apart, thetotal bottom width of the member.

As may be most clearly seen from FIG. 3, the completed guard railprovides a continuous inclined at metallic side wall which, at its neck4 merges into the bulged top S of the guard. When concrete is employedit will completely hide and protect the bolts 15 and tie clips.

The function of this bulge may be shown by considering a 20 to 50approach to the member by a vehicle, which approach may have beenoccasioned by a drivers dozing and wandering from his former drivingposition toward the extreme left of the road, by a very sharp squeeze onthe vehicles right in passing or maneuvering, or as a result of anactual side-swipe or violent mechanical forcing of the vehicle againstthe guard member. In this situation, the bumper or other metal parts ator about the height of the bumper above the road, will establish andmaintain effective contact between the lower area of the bulge of theguard member and the vehicle. The bumper or striking portion of thevehicle will thus be unable to rise above the outwardly curving bulge atthe top of the guard rail.

The guard member, when illed with concrete, weighs approximately 1.6tons for every lineal feet and is tied down to the pavement with boltswhich in this same lineal distance, if the bolts are made of ordinarysteel, have a capacity to resist an upward pull of 50 tons. A high speedglancing collision against the guard member tends to apply pressure overa continuing lineal footage of guard member if the struct-ure of thecolliding vehicle gradually collapses by severe impact, with the resultthat the impact may be applied against as much as 30 or 40 lineal feetof guard member. Since the members have externally slick andblemish-free skin plates, there is no interference with the forwardcomponent of a vehicle colliding against them. On the contrary, theyoperate to stop only, and completely, the lateral component of motion bya colliding vehicle which Iwould tend to carry that vehicle into theon-coming line of traic.

Referring to FIGS. 7-12, inc., modifications of the guard rail of theinvention are shown in respect of the tie or clip arrangement.

Referring particularly to FIG. 7, a guard rail member is il-ustratedgenerally similar to that of FIGS. -6v. However, in place of the uppertie Aclips 7a, 7b, of the latter figures, two opposed trough clips 22 or22a are welded as at 22C to the interior surfaces of the neck portions 4of the skin-plates 1 and 2. A special washer member 23 is provided,having at its opposite end, downwardly extending flanges, as at 24a,2412, these flanges being inserted in the trough clips, respectively.Washer member 23 has a central aperture 25, FIG. l2, for receiving thebolt 15.

As indicated above, two forms of trough clips are shown in FIG. 7. Inthe one form, trough clip 22 is provided with an aperture 26 at itsbottom. In the other form, trough clip 22a is closed at its bottom. Thestructure of FIG. 7 has a particular advantage in that it eifects areduction in the amount of metal required for the clip and washerassembly. Y

FIG. 8 illustrates a further modification of the inven tion, somewhatsimilar to that of FIG. 7. However, here trough clips 27 are employed,which clips are of hairpin cross-section. These clips extendcontinuously for the full length of the skin plates. This structure hasthe special advantage of enabling greater exibility in the positioningof the clip and bolt assembly, and the positioning of the skin plates ofthe members with regard to their registry one with the other.Furthermore, if the members are to be filled with concrete, the tro-ughclips 27 serve as additional reinforcement members.

FIG. 9 shows a still further modication in which the skin plates 1, 2,rthemselves are formed near the t-op with trough-like portions 1a, 1b.These trough-like portions are positioned at a height corresponding tothe height of the neck portions 4 of the other forms of the inventiondescribed. In the modification of FIG. 9, the plate member 23 isprovided with flanges 24a, 24b, which extend into the troughs 1a, 1b,and in addition is preferably somewhat deeper at its center portion 28than the corresponding washer members of FIGS. 7 and 8. Between itscenter portion 28 and the flanges 24a, 241;, in each side are rounded`channels 29a, 291;, adapted to engage the correspondingly roundedportions 30a, 30h, of the skin plates. As indicated by the dashed` line15b, the modifications of FIGS. 7-9 may employ in addition to avertically disposed bolt 1'5, the modification in which these bolts aredisposed at angles. If such an angle bolt arrangement is employed, theupper surfaces of the washermember 23 will be modified as shown by theydashed,

line 13b.

In FIGS. 13 and 13a there is shown my preferred center roadway guardrail or barrier consisting of two identical metallic skin plates 31.-Each skin plate is formed of a straight, or flat, inclined side, whichside merges into a relatively short upwardly extending, vertical neckportion 31X, the latter merging intoan upper curved head portion. Theopposed head portions of the skin .plates 31 at their ends turn inwardlyso as to form a central top -opening 36. Welded continuously to theinner lower surfaces of the neck portions 31X are pairs of opposedinclined strips 32. These attached strips pro-vide continuous hold-downand spacing lines of pressure application near the top of the barrier.Special tie members 34 are provided and these members have grooves 34afor receiving the strips. In the embodiment shown each tie member 34 isformed with at least one aperture adapted to receive a prestressedanchor bolt 35, which is shown in vertical position in FIG. i3. In orderthat the anchor bolt 35 may have alternately inclined locations asindicated at 35X, tie member 34 may be of a type formed with a slopedhole and inclined top face as at 13b, FIG. 9, so that by turning the tiemember the sloped hole previously arranged for inclination of the anchorbolt at one side of the structure may provide for a like inclination ofthe anchor bolt at the opposite side of the structure. Also the tiemember 34 may be provided with a central vertical hole and with twosloped holes extending in opposite inclinations, or a single sloped holein addition to the center vertical hole.

Vertical anchor bolts are used generally, except where the barrier has'to be placed over longitudinal asphalt expansion joints in the roadpavement. Where this occurs, the anchor bolts are set on a slope,successively alternating right and left by placing successive members 34with the slope of the bolt hole alternating.

The barrier is secured to the roadway pavement, and held in properalignment position against impact shock from out-of-control vehicles bymeans of threading the anchor bolts 35 into expansion anchors 37 setinto previously drilled holes in the concrete pavement 38.

The continuous steel strips 32 which support and interlock with the tiemembers 34 are weld-ed to the inside of the neck 31X ofthe plates 31 atan angle 34e the bisector of which is a projection of the center of theassociated sloped barrier side -plate 31, and the points at the apex ofthe angle 34C of the tie member margins, exterior the grooves, are inline with the center line of the thickness of the plates 31. Thiseliminates eccentric loading on the side plates and materially helps toprevent buckling thereof when the successive anchor bolts arepre-stressed before the barrier is filled with yconcrete or othercementitious material, the latter being indicated at 42a in FIG. 13.Stiffeners 41a of substantially Z section, and welded to the skin plates31 at longitudinally spaced intervals, bond these plates to cementitiousfiller 42a, thus to lock the skin plates t-o the filler and therebyreinforce the barrier. The weight of the concrete fill, together withthe weight of the steel parts of the barrier, aids materially inpreventing its overturning under lateral impact shock.

The plates 31 are turned inward at the base to form continuous lines ofa hook-type interlock 39 to be engaged by specially formed wide steelspreader-tie plates 40 Which are placed into the barrier duringinstallation at approximately 30 on centers. These lower spreader-tieplates hold the barrier side plates firmly in position and insureperfect alignment of the base of the barrier along its predeterminedlocation. The spreader tie plates 40 are provided with upturnedstiifener edges 41 which terminate in outwardly projecting lportions 42,which prevent the tie plates 40` from jumping out of an interlock 39after the skin plate 31, during assembly, has been rotated from the roadinto position. This construction facilitates and speeds up installation.

It is preferred that the barrier have the following dimensions: A basewidth at roadway surface of 221/2; the over-all height of 26" which isfrom l" to 31/2" higher than center of gravity of automobiles of currentdesign; and the steel armoured sides of the barrier should rise from thepavement at a slope angle of 65% This slope is sufficiently steep toinhibit car wheels from mounting it, especially in view of the very lowfriction factor that will develop between rubber tires and smooth steelsurfaces such as the barrier sides. The barrier side slope of 65% fromthe pavement level permits car wheels to travel along and in directcontact with the bases of the barrier without scraping any part of thecar body or chassis against the higher-up portions of the barrier.

The side plates 31 preferably are of 20 foot long sheet steel plates,butt-ended together to form the indicated barrier shape, the spacebetween being filled with poured concrete.

The short vertical neck 31X which then widens out to form a continuoushorizontal ledge Sly has the function of catching the bumper of a carthat may be thrown against the barrier at, or near, a right angleapproach, FIG. 13 showing the normal height of current car bumpers.

As will be observed in FIG. 13, there is an area 31X which issubstantially perpendicular to the horizontal area Sly related to thetop area. v

Thebarrier can be installed as shown directly on pavements whether thepavement is level or on slight vertical or horizontal curves. It can beequally well installed on sharper short radius horizontal curves bymerely shortening the horizontal (longitudinal) length of the sideplates as required. It can also be installed on top of and along theside edges of curb height o-r higher raised central platforms ofroadways. In such cases the sloped side plates would be carried downbelow the edge of the platform to the roadway level.

Successive short steel dowel rods extending from the larger body of theconcrete below the neck of the barrier and up into the flanged, narrowerhead may be inserted following the pouring of the concrete to assist inpreventing damage to the barrier from future excessive impact shocks.

The shape, general dimensions, and -design of the barrier are such that:

It forms a true insurmountable and unstraddleable barrier.

It will guide an out-of-control automobile into a flatter deflectionangle than the original approach angle and, under certain conditions ofimpact angle, redirect and guide the vehicle unharmed in continuousprogressive contact along the barrier to provide guided vehiculartravel.

It prevents jump and bounce of the car after impact such as are producedby ordinary curbs or by gentle or curving barrier slopes and willtherefore help irnmensely to prevent car overturn.

Since rubber on steel, painted or unpainted, produces a very lowfriction factor, a car wheel can roll and slide along the steel barriersides Without materially reducing the cars forward Velocity.Consequently, there is very little tendency to climb the barrier even onfairly wide approach angles.

It can be quickly installed and opened to traf-lic almost immediately.

It is made of standard parts which can be readily stocked and theinstallation in a dangerous section of roadway can therefore be madealmost immediately.

As shown on the drawings, the barrier shape permits cars moving inopposite directions to pass each other within only 9 between the carbody sides.

The projecting ledge at the head of the barrier positively prevents acar from surmounting or straddling this barier even when the car isforced or thrown against it by a previous `collision with another car orobject on its own side of the roadway.

By virtue of the comparatively wide base for the short cantilever heightof the barrier, impact stresses produced by a collision against it areimmediately distributed over a fairly long length of the barrier. Thisquick distribution of impact stresses is assisted by pre-tensioning theanchor bolts-thus pre-compressing the skin plates before filling withcementitious material-which materially reduces the danger of localizedimpact damage to the barrier at point of contact.

While in actual practice, operation of the barrier of the presentinvention involves a considerable number of variables and a rathercomplex interplay of forces, it will be appreciated that the principlewhich underlies this operation is based upon the dissipation of selectedportions of an impinging vehicles kinetic energy. That is, the barrieroperates by reacting against and causing dissipation of -only thelateral component of the vehicles energy, i.e., that component which isdirected perpendicularly to the direction along which the barrierextends. At the same time, due to the smooth, fiat and friction freeouter surface of the barrier an-d the continuous and rigid manner inwhich this surface is supported, it produces substantially no effect onthe orthogonal or longitudinal energy component of the impingingvehicle. It is important to note that for a vehicle which veers from thenormal course of trafiic and into the barrier, the energy associatedwith the longitudinal component is over ten times as lgreat as thatassociated with the lateral component. Also, since the longitudinalcomponent is not dangerous in itself, it need not be controlled orrestricted by the barrier.

As indicated previously, the barrier operates to cause dissipation of avehicles Alateral kinetic energy by directing such energy through thesuspension system of the vehicle and into its shock absorbers. As thevehicle moves against the barrier, the sharp incline of the barriersouter surface causes the impinging wheel of the vehicle to slip rapidlyupward so as to compress its supporting spring and to flex its shockabsorber. This llexing of the shock absorber dissipates a portion of thelateral kinetic energy while the remainder of this energy is convertedto potential energy .Of compression of the supporting spring. Thesteepness and smoothness of the barriers inclined surface, however, istoo great to permit the risen wheel to remain at its elevated position;and consequently, the `wheel immediately slides back down While itssupporting spring expands and its shock absorber unexes. At the sametime, the other wheels which are on the roadway, are caused to sliplaterally` away from the barrier. The lateral sliding of the vehicleswheels and the flexing and unflexing of its shock absorbers dissipatesthe remainder of the undesired lateral kinetic energy.

It will be appreciated that unless the vehicle wheel or wheelscontacting the barrier slip back down to the roadway immediately afterlbeing forced up the barrier side, the thus compressed vehicle springwould begin to eX- pand in a direction causing swerving and rolling ofthe vehicle body in an uncontrollable manner.

In order to ensure this wheel slip down it will be understood that thebarrier inclination angle must be at least equal to the sum of theangles which correspond to the two frictional factors opposing suchwheel slip down. That is, the barrier inclination angle must be at leastas great as the sum of the angles whose tangents are equal,respectively, to the wheel-to-barrier and wheel-to-roadway frictioncoefficients. Of course, the barrier inclination must not be so greatthat the wheel-to-barrier friction is able to prevent wheel slip up inthe tirst place. Thus, the barrier inclination must be no greater thanthe angle whose tangent is equal to the reciprocal of thewheel-to-barrier friction coefficient.

It can readily be appreciated that the lower the variousfri-ctioncoefficients happen to be, the greater will be the range of barrierinclination angles which will give proper operation; and conversely, asthe frictional values increase, a point is reached where no barrierinclination will permit both slip-up and slipdown of an impingingvehicle wheel, While friction coefficients vary from tire to tire,roadway to roadway and even from time to time in individualcircumstances; it is commonly known that for large numbers of individualcircumstances such variations occur within fairly well defined limits.For example, rubber tires on roadway pavements exhibit, under normalconditions, a friction coefficient between 0.6 and 0.9, the most commonbeing about 0.75; and rubber tires on metal, such as steel or paintedsteel surfaces subjected to normal weather conditions, will exhibit afriction coefficient between 0.35 and 0.65, the most common being about0.4.

From this, it can be expected that a barrier having a smooth, slick,outer surface and used in conjunction with lower friction pavements,will perform in the manner described when its inclination angle isbetween 50 and 71. However, in order to accommodate a greater rangev ofpavement types, and in order to relieve somewhat the low frictionrestrictions required of the barrier surface,

it is believed that a barrier inclination angle of between 59 and 68will perform most satisfactorily; and an inclination angle ofapproximately 66 will accommodate the greatest variation of othervariables.

The barrier height must, of course, be suicient 4to enable the barrierto present to the Wheels of an impinging vehicle an inclination angle`within theabove indicated ranges. It will be appreciated that if thetotal barrier height is much below the vehicle wheel axle level, theinclination angle of the barrier is not effectively presented to thewheel, for the wheel would contact the top of the barrier only. In sucha situation the slip-up and slipdown mode of operation whichcharacterizes the present invention cannot take place, for in such casethe vehicle wheel would mount and be held up on top of the barrier.While the wheel axle level determines the minimum barrier heightrequired to achieve the desired mode of operation, it is to be notedthat the invention is not practically operative unless the height of thebarrier is such that the effective angle presented to the vehicle wheelis maintained within the aforementioned range over the entire distanceof wheel slippage up the barrier surface. Thus,

while under certain special circumstances a barrier may be made toperform according to the aforedescribed principles at a height of only13 inches, for conventional roadway traic it is `preferred that theinclined barrier surface extend to a height of approximately 20 inchesabove the roadway.

The bulge at the top of the barrier serves, in cases of extreme lateraivelocities, to prevent traversal of the barrier by the impingingvehicle. This takes place by the bulge either catching on a projection,such as a bumper, or by forming its own projection, as by creasing intothe body skin of the vehicle, at a .point in time before the vehiclebody has risen appreciably. This prevents overturning of the vehicle ortraversal by the vehicle of the barrier. Because the bulge operates torestrain upward body movement before it has reached appreciable velocitythe forces encountered by the bulge are minimized. It can be seen thatin order to operate as above described, the bulge should projecthorizontally outward from the top of the dat inclined barrier surface ata height of 19 inches or more and to a point somewhere above theinclined surface.

This application describes subject matter described and claimed in mycopending applications Ser. No. 584,798, tiled` May 14, 1956, Ser. No.660,129, tiled May 20, 1957 and Ser. No. 55,534, filed Sept. 12, 1960.

What is claimed is:

1. A roadway guard barrier comprising a structure mounted in fixedrelation to and extending longitudinally along a roadway, said structureproviding continuous and rigid support along a smooth continuous outersurface exposed to and inclined obtusely with respect to traffic on saidroadway, said outer surface being flat and rising abruptly and atly fromsuch roadway at an angle between about 50 and about 71 degrees and to aheight of at least 13 inches, said outer surface having frictionalcharacteristics similar to those of finished metal.

2. A roadway guard barrier comprising a structure mounted in fixedrelation -to and extending longitudinally along a roadway, saidstructure providing continuous and rigid support along a smoothcontinuous outer surface exposed to and inclined obtusely with respectto traffic on said roadway, said outer surface being flat and risingabruptly and flatly from such roadway at an angle of about 66 degreesand to a height of approximately 20 inches, said outer surface havingfrictional characteristics similar to those of finished metal. v

3. A non-traversable roadway guard |bar-rier comprising at least oneguard plate, said guard plate having frictional characteristics similarto those of finished metal, fastening Vmeans mounting said guard platetoextend longitudinally along the roadway, said guard plate having asmooth flat and continuous outer surface facingv traffic in obtuselyinclined relation thereto which rises abruptly from the roadway at anangle of from about 50 to about 71 degrees to a height of at least 13inches and means providing continuous rigid support along said guardplate, said angle, height, and frictional characteristics beinginter-related to permit a vehicles tire to slide up said su-rface whensubjected to lateral forces thereaglainst and to prevent retention ofsaid tire up on said surface thereby preventing traversal by animpinging vehicle while producing dissipation of such impinging vehicleslateral kinetic energy through the sliding up and down of such vehiclestire on said outer surface.

4. A non-traversable roadway guard barrier comprising at least one guardplate, said guard plate having a friction coefficient with rubber lessthan 0.65, fastening means mounting said guard plate to extendlongitudinally along the roadway, said guard plate having a smooth atand continuous outer surface facing traffic in obtusely inclined-relation thereto which rises abruptly from the roadway at an anglebetween 59 and 68 degrees to a height of approximately inches and meansproviding continuous rigid support along said guard plate.

5. A non-traversable roadway guard barrier comprising at least onemetallic guard plate, fastening means mounting said guard plate toextend longitudinally along the roadway, said guard plate beingcharatcerized in that it includes a major base area extending from theVroadway along its lower edge and a minor top area contiguous with theupper edge of said base area, the base area being substantially at overits entire area and inclined obtusely on an outer surface facingvehicular tratiic, said outer surface forming a constant acute angle inthe region of from about 50 to about 7l degrees with respect to saidroadway, and rising to a height of at least 13 inches thereabove, saidplate being rigidly supported continuously along said inner surface andhaving a smoot-h, slick and blemish free external surfacewhich avoidsinterference with a colliding vehicles component of motion parallel tosaid plate,and"which operates to stop only, and completely, suchcolliding vehicles component of motion laterial to said plate, the toparea of said barrier being constituted as an outwardly directed bulge ofsaid su-rface, said bulge being constructed and arranged to be engagedby a vehicle in -contact with and moving upwardly along said base area,and said base area projecting towards said roadway beyond the bulge ofsaid top area.

6. A non-traversable roadway guard barrier comprising at least onesmooth steel guard plate, fastening means mounting said guard plate toextend longitudinally along the roadway, said guard plate beingcharacterized in that it includes a major base area extending from theroadway along its lower edge and a minor top area contiguous with theupper edge of said 'base area, the base area being substantially flatover its entire area and inclined obtusely on an outer surface facingvehicular traic, said outer surface forming a constant acute angle ofabout 66 degrees with respect to said roadway, and rising to a height ofapproximately 20 inches thereabove, said plate being rigidly supportedcontinuously along said inner surface and having a smooth, slick andblemish free external surface which avoids interference with acolli-ding vehicles component of motion parallel to said plate, andwhich operates to stop only, and completely, such colliding vehiclescomponent of motion lateral to said plate, the top area of said barrierbeing constituted as an outwardly directed bulge of said surface, saidbulge being constructed and arranged to be engaged by a vehicle incontact with an moving upwardly along said base area, and said base areaprojecting towards said roadway beyond the bulge of said top area.

7. A non-traversable roadway guard barrier comprising a pair of metallicguard plates fastened in opposed relationship to extend longitudinallyalong the roadway, said plates including major base portions which aresubstantially at over their entire area and which are inclined towardand space for each other to form therebetween a barrier base .portion ofsubstantially tr-apezoidal crosssection, said major base portions beingabruptly inclined with respect to said roadway, forming therewithconstant internal angles between about 50 and about 71 degrees andrising to a height of at least 13 inches above the roadway, and meansbetween said guard plates providing continuous rigid support therefor.

8. A roadway guard barrier comprising a pair of opposed guard platesfastened on the roadway, said plates including base portions thereofwhich are inclined toward and spaced away from each other to formtherebetween a base portion of said barrier of substantially trapezoidalcross-section, the outwardly facing surfaces of said plates being smoothand having a low friction coefficient, said plates including a reverselycurved top portion of each formed as an outwardly directed bulgethereof, each said plate projecting toward the roadway beyond the bulgethereof, upper and lower separable connector means extendingrespectivelybetween the tops of the base portions and between t-he bottoms of thebase portions of said plates to secure said plates in predeterminedspaced relationship, anchor elements extending through aligned aperturesin said upper and lower separable connectors and anch-oring said barrierto said pavement.

9. A roadway guard barrier comprising, opposed elongated plates eachhaving a substantially flat majo-r wall area inwardly inclined upwardlytowards that of the opposed plate, and ea-ch plate having at the top aminor wall area turned outwardly and thence inwardly to provide a bulgedflange, the upper ends of said minor wall area being spaced to providean inlet aperture therebetween,v inwardly projecting tie members carriedby the inner face of each plate 4adjacent the upper region thereof atsaid minor area and also at the lower marginal areas of said plates, oneof said upper tie members and one of said lower tie members overlappingthe other of said upper and lower tie members, respectively, said upperand lower tie members having aligned apertures therein, bridging meansextending between opposed plates adjacent said upper tie members andmaintaining same in spaced apart relationship against inward collapse,said bridging means having an aperture therethrough in alignment withthose in said tie members, means extending downwardly through saidaligned apertures in said tie members and said bridging means andanchored in the surface below said plates to exert a downward force uponsaid plates, and a cementitious filling material disposed between t-heplates from wall to wall of the opposed surfaces, said filling materialbeing hardened and formed in transverse section as a wedge having majorrelatively straight inwardly inclined side walls merging into a minor vbulged top area.

10. A roadway guard barrier comprising, opposed elongated plates eachhaving a substantially flat major wall area inwardly inclined upwardlytowards that of the opposed plate,v and each plate having at the top aminor wall area turned outwardly and thence inwardly to provide a bulgedflange, the upper ends of said minor wall area being spaced to providean inlet aperture therebetween, inwardly projecting tie members carriedby the inner face of each plate adjacent the upper region thereof atsaid minor area and also at the lower marginal areas of said plates, oneof said upper tie members and one of said lower tie -members overlappingthe other of said upper and lower tie members and having alignedapertures therein, bridging means extending between op-posed platesadjacent said upper tie members and maintaining same in spaced apartrelationship against inward collapse, said bridging means having an'aperture therethrough in alignment with those in said tie members, andmeans extending downwardly throng-h said aligned apertures in said tiemembers and said bridging means and anchored in the surface below saidplates to exert a downward force upon said plates.

11. In a roadway guard barrier -comprising opposed elongated plates eachhaving a substantially at major wall area inwardly inclined upwardlytowards that of the opposed plate, and ea-ch plate having at the top aminor wall area turned outwardly 'and thence upwardly and inwardly toprovide a bulged flange, the upper ends of said minor wall a-reas beingspaced to provide an inlet apertu-re therebetween, inwardly and upwardlyprojecting strips secured to the inner face of each plate adjacent theregion of said bulged flange, and extending longitudinally thereof, atie member extending between opposed plates and maintaining same inspaced relationship, said tie member having downwardly opening groovesreceiving the strips secured to the opposed plates, the lower ends ofsaid side plates being turned inwardly and thence outwardly to delineopposed hook portions, transverse fastening means formed with hook meansat their ends cooperating with said opposed hook portions to maintainsaid side plates in proper spaced alignment, and means extendingdownwardly through said tie member and said transverse fastening meansand anchored in a surface below said plates to exert a downward forceupon said plates.

12. A roadway guard rail barrier comprising a pair of opposed guardplates supported on the roadway, said plates including base portionsthereof which are inclined toward and Vspaced from each other to formtherebetween a -base portion of said barrier of substantiallytrapezoidal cross-section,` the outwardly facing surfaces of said platesbeing smooth and having a low friction coeicient, said plates includinga doubly, reversely curved top portion of each, which extends rstdownwardly and substantially parallel to said base portion and thenceupwardly and outwardly away from said base portion to form an outwardlydirected bulge means maintaining the lower portions of said guard platesin spaced relationship, and apertured anchor plates extending betweensaid guard plates at spaced intervals therealong, said anchor plateshaving grooved undersurfaces seating on the ridges formed by the tirstreverse curvature of said guard plates, and having terminal lugs seatingin the grooves formed between the first and the second reverse curvatureof said guard plates, respectively, and means securing said guard platesto said -roadway comprising roadway anchor bolts extending through theapertures of said anchor plates and secured thereto.

13. A roadway guard rail barrier comprising a pair of opposed gua-rdplates supported on the roadway, said plates including base portionsthereof which are inclined toward and spaced away from each other toform therebetween -abase portion of said barrier of substantiallytrapezoidal crosssection, the outwardly facing surfaces. of said platesbeing smooth and having a low friction coeicient, said plates includinga top portion of each which extends rs-t upwardly substantiallyperpendicular to t-he roadway and thence in reverse curvature firstoutwardly and upwardly and thence inwardly, anchoring strips secured tothe inner surfaces of each guard plate where it begins to extendupwardly from its inclined base portion, ea-ch said strip being disposedat an angle to said verticalportion to form a groove therebetween,spreader tie plates extending between said strips at spaced intervals-therealong, said plates having grooved terminii on their under sidesfor seating upon said strips and in the groove formed therebetween andtheV associated guardv plate, each said guard plate having at its basean inwardly and thence upwardly turned base portion for seating on saidroadway, and hook'like spreader tie plates extending between the baseportions of said guard plates at spaced intervals therea'long andinterlocking with the inner and upwardly turned portions of said guardplates, respectively.

References Cited by the Examiner 4 UNITED STATES PATENTS 1,021,0823/1912 Wright et al 94--18 1,606,588 11/ 1926 Meermans 94-31 1,726,2678/ 1929 Higgins 94-1.5 2,135,400 11/1938 Johnson 94-1.5 2,153,392 4/1939Robertson 9 4-l.5 2,279,942 4/ 1942 Hansherr 256-13.1

FOREIGN PATENTS 225,676 2/ 1958 Australia.

OTHER REFERENCES Highway Research Board, June 24, 193 8, 13. 343.Highway Research Board, Jan. 17-20, 1956, pp. 22 and 25.

JACOB L. NACKENOFF, Primary Examiner.

1. A ROADWAY GUARD BARRIER COMPRISING A STRUCTURE MOUNTED IN FIXEDRELATION TO AND EXTENDING LONGITUDINALLY ALONG A ROADWAY, SAID STRUCTUREPROVIDING CONTINUOUS AND RIGID SUPPORT ALONG A SMOOTH CONTINUOUS OUTERSURFACE EXPOSED TO AND INCLINED OBTUSELY WITH RESPECT TO TRAFFIC ON SAIDROADWAY, SAID OUTER SURFACE BEING FLAT AND RISING ABRUPTLY AND FLATLYFROM SUCH ROADWAY AT AN ANGLE BETWEEN ABOUT 50 AND ABOUT 71 DEGREES ANDTO A HEIGHT OF AT LEAST 13 INCHES, SAID OUTER SURFACE HAVING FRICTIONALCHARACTERISTICS SIMILAR TO THOSE OF FINISHED METAL.